As a flexible package bag provided with a liquid pouring nozzle of a self-sealing non-return function made from plastic films or a film-shaped one-way pouring nozzle, there are bags as disclosed in JP-A-2005-15029 and JP-A-2005-59958 proposed by the inventors. Since these flexible package bags are non-self supporting type package bags made from soft laminate films, they are inconvenient in use alone as they are and have taken a form of housing and fixing in a container as disclosed in JP-A-2004-196364.